Add memory-alert plugin for Claude Code process memory monitoring

[tiwari91]

Summary

• Adds a new memory-alert plugin that monitors Claude Code's own process memory and alerts in the terminal when it exceeds a configurable threshold
• Sums RSS (resident set size) of all running claude processes via ps
• Works on both macOS and Linux
• Uses a PostToolUse hook — lightweight check runs after each tool call
• Default threshold is 5GB, configurable via MEMORY_ALERT_THRESHOLD_GB environment variable
• Non-blocking: alerts are informational only, never interrupt workflow

Plugin structure

plugins/memory-alert/
├── .claude-plugin/
│   └── plugin.json
├── hooks/
│   ├── hooks.json
│   └── scripts/
│       └── memory-alert.sh
└── README.md

Example output

[MEMORY ALERT] Claude Code memory usage: 5.2GB (threshold: 5GB) — consider closing idle sessions

Test plan

• Tested on macOS (Darwin) — correctly sums Claude process RSS and alerts above threshold
• Verified alert is silent when memory is below threshold
• Verified MEMORY_ALERT_THRESHOLD_GB env var overrides the default
• Test on Linux